Compander IC MM1102 MITSUMI Compander IC Monolithic IC MM1102 This IC was developed for use in cordless telephones. It is a compander IC incorporating compressor/expander circuits for a significant noise reduction effect without complicated external circuitry. On the transmission side, the dynamic range of audio signals is compressed by the compressor circuit; on the receiving side, the expander expands the signals. As a result the dynamic range over the transmission channel is reduced logarithmically by one-half. Features 1. Can be driven at low voltages (down to 2.4V) 2. Internal mute function 3. Internal limiter (IDC) function 4. Two internal op-amps (for splatter filter) 5. Internal standby function 6. Data input, output pins 7. Independent mute circuit Package SSOP-24A (MM1102XF) Applications 1. Cordless telephones 2. Various mobile communication devices Pin Assignment 24 23 22 21 20 19 18 17 16 15 14 13 1 2 3 4 5 6 7 8 9 10 11 12 SSOP-24A 1 C.Vref 9 C.OUT 17 E.MUTE SW 2 C.IN 10 BUFIN 1 18 E.OUT 3 C.IN- 11 BUFOUT 1 19 E.RECT 4 C.RECT 12 GND 20 A.OUT 5 C.RIN 13 BUFIN 2 21 A.IN- 6 C.FB 14 BUFOUT 2 22 A.IN+ 7 C.NF 15 STANDBY SW 23 E.Vref 8 DATA IN 16 C.MUTE SW 24 VCC MITSUMI Block Diagram Compander IC MM1102 Compander IC MM1102 MITSUMI Pin Description Pin no. DC voltage I/O resistance Function 1 1.5V - Regulator output 23 1.3V - 1PIN···C.Vref 23PIN···E.Vref 2 1.5V 100kΩ Mike amp unit 3 1.5V 2.2kΩ Mike amp input stage 4 - 10kΩ Rectifier circuit unit 19 - 10kΩ Attack and release times determined 5 1.5V 15kΩ Rectifier circuit unit Input pin 6 1.5V - Compressor amp unit 7 1.5V 10kΩ 6PIN···Output pin 7PIN···Feedback resistance 8 1.5V 100kΩ Inverting amp (0dB) 9 1.5V - 8PIN···Input pin 9PIN···Output pin Equivalent circuit Compander IC MM1102 MITSUMI 10 (13) 11 (14) 12 15 - - Buffer amp unit Pin 10 (13): Input pin not biased internally - - 0V Vcc (3V) Pin 11 (14): Output pin GND pin 150kΩ Standby SW The IC operates at approx. VCC-1 V and below. At open and high (VCC) levels, it is in the standby state. 16 0.7V - Compressor · expander 17 0.7V - Mute SW Muted at approx. 0.6V and below; operates normally at open and high levels 18 1.3V - Expander unit Output pin 20 - - Pin 20: Output pin 21 - - Input amp 22 - - Pin 22: Input pin (+) Pin 21: Input pin (-) None of these are biased internally Compander IC MM1102 MITSUMI Absolute Maximum Ratings (Ta=25°C) Item Symbol Ratings Units Storage temperature TSTG -40~+125 °C Operating temperature TOPR -10~+70 °C Power supply current VCC max. +2.4~+8 V Allowable loss Pd 450 mW Electrical Characteristics (Except where noted otherwise, Ta=25°C, VCC=3V, fIN=1kHz) Item Min. Typ. Max. Units 4.4 6.5 mA IsCC 0 10 µA Threshold voltage Vth 0.65 Input reference level Vinc VOC=100mVrms, VIN=0dB 8.0 13.5 Gc1 VIN=-20dB -0.5 0 0.5 dB Gc2 VIN=-40dB -1.0 0 1.0 dB Distortion THDC VIN=0dB 0.3 1.0 % Output noise voltage Vnc No signal (CCITT) 2.5 5.0 mVrms Mute attenuation Attc VIN=0dB, Mute SW : on -50 -40 dB Limit voltage Vlimc THD=10% 1.15 1.3 1.45 VP-P DATA pin voltage gain GDATA VIN=0dB, Mute SW : on -0.5 0 0.5 dB DATA pin maximum output VD max. THD=10%, Mute SW : on 0.70 Crosstalk CTC EXPVIN=0dB -33 -28 dB Ripple rejection ratio RRC VR=100mVrms, fR=1kHZ -23 -18 dB Consumption current ICC Standby current consumption Gain error difference Compressor unit Symbol Measurement conditions * No signal V 18.0 mVrms Vrms Compander IC MM1102 MITSUMI Electrical Characteristics (Except where noted otherwise,Ta=25°C, VCC=3V, fin=1kHz) Item Symbol Measurement conditions Vine Voe=100mVrms, VIN=0dB 25 35 50 mVrms Ge1 VIN=-10dB -0.5 0 0.5 dB Ge2 VIN=-20dB -1.0 0 1.0 dB Ge3 VIN=-25dB -1.5 0 1.5 dB Distortion THDe VIN=0dB 0.15 1.0 % Maximum output voltage Ve max. THD=10% Output noise voltage Vne No signal (CCITT) Mute attenuation Atte VIN=0dB, Mute SW : on 60 70 Input amp voltage gain GI VIN=0dB 14.6 15.6 Input amp maximum output Veo max. THD=10% 0.90 1.10 Crosstalk CTe COMPVIN=0dB -75 -60 dB Ripple rejection ratio RRe VR=100mVrms, fR=1kHz -60 -50 dB Buffer amp gain Gba Voba=100mVrms -1 0 +1 dB Buffer maximum output voltage Voba max. THD=10% 0.35 0.50 Vrms COMP reference voltage C.Vref 1.5 V EXP reference voltage E.Vref 1.3 V Input reference level Gain error difference Expander unit Min. Typ. Max. Units * 550 mVrms 700 20 40 µVrms dB 16.6 dB Vrms +20dB) -V G (dB) *Gain error difference = (VG : COMP=0.5, EXP=2 OUT IN Function Description 1. Compressor unit The compressor unit consists of the mike amp, compressor, limiter circuit, data amp, and mute circuit. The mike amp gain can be adjusted through an external resistance, and so the mike amp can be connected directly to a microphone. An internal limiter circuit to prevent overmodulation as well as a data amp (0dB amp) enabling transmission of data signals without compression are also provided. Switching between audio signals and data signals is possible using the compressor mute switch. 2. Expander unit The expander unit consists of an input amp, expander, and mute circuit. The input amp makes available all input and output signals at pins, and so can be used freely as an amplifier, filter amp, or data amp. When used as a data amp, the expander mute switch can be set so that the expander output is nearly silent. MITSUMI Compander IC MM1102 About Application Circuits 1. Mike amp The compressor unit mike amp is exposed to circuits outside the IC via positive and negative input pins. The positive input pin is connected to C.Vref by a bias resistance of 100kΩ, so that no external bias is needed. he internal configuration appears in Fig. 1. When pin 4 is open the gain is lowest, and an input voltage of approx. 13.5mVrms is the reference level. When the external resistance is 0Ω, the gain is maximum. The internal configuration appears in Fig. 1. 2. Rectifier circuit unit (rectifier) The product of the external capacitance and the internal resistance (10kΩ) determines the time constants for the attack and release times. 3. Compressor amp The compressor amp requires that the DC gain be unity and the AC gain be infinite. In order to satisfy this requirement, AC feedback is eliminated and only DC feedback is used. In order that only DC feedback be present, a capacitor to eliminate AC components is connected to pin 8. The cutoff frequency is determined by the product with the internal resistance (10kΩ). 4. Compressor data amp The data amp uses an inverting amp. The internal input resistance is 100kΩ, and the DC bias voltage is 1.3V. The compressor mute switch at pin 15 is used to switch between data signals and audio signals. MITSUMI Compander IC MM1102 5. Expander input amp The positive and negative input pins and the output pin are exposed to circuitry outside the IC. The expander input amp can be used as a signal amplifier, a buffer amplifier, and a filter amp. By taking the signal from this amp's output pin, the data signal can be obtained without passing through the expander. If the expander mute switch is turned on, this signal can be prevented from appearing in the expander output. 6. Mike amp input switch and mute switches The internal equivalent circuit for each of these switches appears in Fig. 6. 7. Standby switch The internal equivalent circuit for the standby switch appears in Fig. 7. Compander IC MM1102 MITSUMI Measuring Circuit (Except where noted otherwise, VIN=1kHz) 1. Consumption current 5. Distortion 2. Threshold voltage 6. Limit voltage 3. Input reference level 7. Maximum output voltage 4. Gain error difference Gain error difference= (VOUT (dBv) -20dB) -VIN (dB) (G=COMP=0.5, EXP=2) Gain error difference (1) Gain error difference (2) Gain error difference (3) G Gc1=-20dB, Ge1=-10dB Gc2=-40dB, Ge2=-20dB Ge2=-30dB Compander IC MM1102 MITSUMI 8. DATA pin/Input amp voltage gain 12. Output noise voltage 9. DATA pin/Input amp maximum output 13. Mute attenuation 10. Crosstalk 14. Buffer amp gain 11. Ripple rejection 15. Reference voltage